Optimization of Chromate Reduction by Whole Cells of <i>Arthrobacter</i>sp. SUK 1205 Isolated from Metalliferous Chromite Mine Environment

Arthrobacter sp. SUK 1205 isolated from metalliferous chromite mine environment of Orissa, India showed wide degree of tolerance to heavy metals including Cr(VI), variety of antibiotics and was also capable of reducing Cr(VI) during growth. Freshly grown whole cells of this bacterium were evaluated for chromate reduction under batch culture using Vogel Bonner (V. B.) broth as the base. Cells of SUK 1205 were capable of completely reducing 100 μM Cr(VI) in V. B. broth within 48 h of incubation. Reduction of chromate increased with increase in cell density which attained maximum at 1010 cells/ml, however, reverse was the phenomenon when the concentration of Cr(VI) increased gradually. Glycerol, glycine and glucose promoted chromate reduction efficiency of the cells when used as electron donors. Optimum pH and temperature were found to be 7.0 and 35°C respectively. The process of reduction was inhibited by Ni(II), Mn(II), Zn(II) and Co(II), but Cu(II) and Fe(III) was promotive in nature. On the other hand, 2, 4-dinitrophenol was found to be neither promotive nor inhibitory for the reduction process, but carbonyl cyanide-m-chloro phenyl hydrazone, sodium azide, sodium fluoride and N,N,-dicyclohexyl carboiimide were inhibitory. Cells of SUK 1205 when permeabilized with toluene, triton X-100 and tween 80 showed an enhancement of the process and thereby indicated that reduction of Cr(VI) was mainly associated with soluble component of the cells. Arthrobacter sp. SUK 1205, therefore, showed great promise for use in Cr(VI) detoxification under a wide range of environmental conditions.

Radiological and X-Ray Diffraction Characterization of Bauxite and Rutile Ore Contaminated Environment in Kanam and Wase Mineral Exploration Sites, Plateau State-Nigeria

Two non-destructive analytical techniques (gamma spectrometer and X-ray diffractometer) were employed in the analysis of bauxite and rutile ore and their vicinity soil and control sourced within the Kanam and Wase mineral exploration sites. The activity concentrations of natural radionuclides 238U, 232Th, and 40K in the soil samples received from bauxite and rutile mineral mining vicinities revealed high concentrations of 238U, 232Th, and 40K compared to the control soil samples sourced 500 m away from the mineral exploration vicinities. Radiological detriments RLI, AUI, Hin and Hex unveiled values exceeding the radiation standard concentration (>1) for soil. X-ray diffraction characterization of bauxite ore revealed the interlocking minerals of Bauxite (18)%, Albite (11)%, Garnet (15)%, Illite (6)% and Muscovite (43)% in various proportions obtained within the 2θ range (9.18 to 64.4) and a peak value (intensity, cps) of 3400. Pure bauxite percentage in the ore meets metallurgical grade (15 - 25)%. X-ray diffraction of rutile ore revealed the minerals of rutile (40)%, quartz (21.4)%, ilmenite (27)% and garnet (11.8)% found within the 2θ range (27.5 to 35.6) and a peak value intensity of 31.1 - 100.0 cps also meeting the metallurgical grade of 15% - 25%. The major environmental concern associated with the mineral-sands industry is the radiation hazards, pollution of ground-water sources from heavy metals, mineral transport with heavy equipment’s, dredging operations in fragile coastal area and clearing of vegetation.

Environmental assessment and nano-mineralogical characterization of coal,overburden and sediment from Indian coal mining acid drainage

The deterioration of environmental conditions is the major contributory factor to poor health and quality of life that hinders sustainable development in any region.Coal mining is one of the major industries that contribute to the economy of a country but it also impacts the environment.The chemical parameters of the coal,overburden,soil and sediments along with the coal mine drainage(CMD)were investigated in order to understand the overall environmental impact from high sulphur coal mining at northeastern coalfield(India).It was found that the total sulphur content of the coal is noticeably high compared to the overburden(OB)and soil.The volatile matter of the coal is sufficiently high against the high ash content of the soil and overburden.The water samples have a High Electrical Conductivity(EC)and high Total Dissolve Solid(TDS).Lower values of pH,indicate the dissolution of minerals present in the coal as well as other minerals in the mine rejects/overburden.The chemical and nano-mineralogical composition of coal,soil and overburden samples was studied using a High Resolution-Transmission Electron Microscopy(HR-TEM),Energy Dispersive Spectroscopy(EDS),Selected-Area Diffraction(SAED),Field Emission-Scanning Electron Microscopy(FE-SEM)/EDS,X-ray diffraction(XRD),Fourier Transform Infrared Spectroscopy(FTIR),Raman and Ion-Chromatographic analysis,and Mossbauer spectroscopy.From different geochemical analysis it has been found that the mine water sample from Ledo colliery has the lowest pH value of 3.30,Tirap colliery samples have the highest electrical conductivity value of5.40 ms cm^(-1)Both Ledo and Tirap coals have total sulphur contents within the range 3-3.50%.The coal mine water from Tirap colliery(TW-15 B)has high values of Mg^(2+)(450 ppm),and Br^-(227.17 ppm).XRD analysis revealed the presence of minerals including quartz and hematite in the coals.Mineral analysis of coal mine overburden(OB)indicates the presence both of pyrite and marcasite which was also confirmed in XRD and Mossbauer spectral analysis.The presented data of the minerals and ultra/nano-particles present shows their ability to control the mobility of hazardous elements,suggesting possible use in environmental management technology,including restoration of the delicate Indian coal mine areas.

PROBLEMS AND COUNTERMEASURES OF ENVIRONMENTAL PROTECTION IN COAL MINES

This paper discusses the problems about the environmental pollution of the coal mines in China and analyses the main reasons which caused the pollution of coal mining areas and puts forward the view that we should get rid of our traditional concepts about social development and take the paths of sustained development. This paper also gives the suggestion that strict rules and laws for the protection of environment of the coal mining area should be set up and favourable policies be worked out to promote the improvement of coal mining area’s environment.

New Constraints on the Environmental Impact of Iron Oxides and Lead-Zinc Mines in Red Sea Hills,Egypt

Iron oxides and lead-zinc deposits in host rocks located in ten drainage basins in the coastal plain of the Red Sea,Egypt,have been subjected to important mining activities.The drainage basins were analyzed to estimate the transportations of these minerals. Fourteen soil samples and fifteen plant samples were collected from sites located in the basin and also in neighboring area and chemically analyzed.In

Distribution, Chemical Speciation, and Environmental Risk Assessment of Heavy Metals in Tailings Soils near Dexing Copper Mine, China

To complement information of heavy metals' distribution, chemical speciation, activity and environmental risks in agricultural soils surrounding tailings, a total of 16 samples obtained from the 4 # tailings site of Dexing copper mine of China were investigated. The total concentrations of heavy metals Zn, Fe, Cu, Pb, Cd, Cr, Hg, As, Mn, Ag, Co, and Ni were determined by inductively coupled plasma-atomic emission spectrometry. Chemical speciations of Cu, Cd, and Zn were investigated with the procedures recommended by Tessier(1979). Two different assessment approaches (GB 15618-1995 and risk assessment code, RAC) were employed to estimate heavy metals' environmental risks. Results indicated that heavy metals, especially Cu and Cd were in high levels of accumulation in these samples. Chemical speciation analysis results revealed that Cu was mainly in organic matter bound fraction (ORG) and residual fraction(RES), and Cd was predominantly in exchangeable fraction(EXC), while Zn appeared mainly with the RES fraction. Environmental risk analysis results showed that Cd was in "heavy" pollution level (classification Ⅲ) in almost all samples, which may exert "high" or "very high" environmental risks. Whereas, for Cu, one fourth samples showed "heavy" pollution level, but were located in "low" or "medium" environmental risk ranks. For Zn, many samples were grouped in "light" pollution level (classification Ⅱ), but were related to "medium" and "high" environmental risk ranks. These results indicated heavy pollution and high environmental risk of Cd in soils surrounding the 4# tailings site, which should be paid more attention to. Meanwhile, for Cu and Zn, the contrary results obtained by different environmental risk assessment approaches, may suggest that a more scientific, adequate environmental risk assessment criterion should consider both total content and chemical speciation activity of heavy metals.

Geochemical and Environmental Evaluation of Um Shashoba Gold Mine Area,Southeastern Desert,Egypt

A suite of elements（Ag,Au,Ba,Bi,Cd,Co,Cr,Cu,Ga,Hf,Hg,Mn,Mo,Ni,Pb,Rb,Sb,Se, Sr,Te and Zn）,total organic carbon（TOC）and pH were analyzed in stream sediment and tailing samples from Um Shashoba area,in order to evaluate Au placer and the sediments being impacted by old mining activities.Analytical results were examined using statistical,graphical and mapping methods.In spite of the results revealing that Au and most of the elements in sediments were in general significantly lower than those in tailing,Au was concentrated in the NE and SW parts forming Au placer.It is remarkably a close association of Au with Hg and Sb;both are useful as pathfinder elements for Au placers.Values of pH could not control a fate of analyzed elements,whereas TOC and Mn oxides and hydroxides could uptake some elements Au,Ba,Co,Cr,Hg,Ni,and Sr.The results also indicated that the sediments were contaminated by anthropogenic factors causing moderate,strong to very strong pollution with respect to Bi,Se and Te,respectively.Additionally,geogenic factors could also contribute elemental enrichment to the drainage system and cause significant toxicity level.

Importance of Public Engagement in Environmental Impact Assessments (EIAs) and the Benefits of Stakeholder Involvement in Project Design, Environmental Soundness, and Social Acceptability

The paper discusses the importance of public engagement in environmental impact assessments (EIAs) and the benefits of stakeholder involvement in project design, environmental soundness, and social acceptability. It highlights the negative repercussions of mining activities in Ghana, including health consequences such as skin conditions, fever, coughs, diarrhea, malaria, and catarrh, as well as HIV/AIDS infection among those engaged in or connected to prostitution in mining towns. The environmental effects of mining in Ghana include noise pollution from heavy trucks, contamination of water bodies with chemicals from mineral refining, pollution of agricultural soils leading to reduced food productivity, and wildlife depletion from deforestation. The activities of small-scale miners, particularly those engaged in illicit mining, have a negative impact on water quality and increase the cost of water treatment for public consumption. Mining operations have detrimental effects on the social, cultural, and natural ecosystems in Ghana, affecting the quality of life of local communities. The study takes into consideration the impact of mining activities on the environment and natural resources in Ghana, as these are vital to the livelihoods of Ghanaian communities. Stakeholders in Tarkwa claim that mining operations have distorted the natural path of the river, leading to excessive pollution and making the water unfit for consumption. Ghana’s economy depends heavily on mining, which also contributes significantly to GDP and generates jobs for a large number of people. But mining also has a lot of negative repercussions, the effects of mining extend beyond the mineralized zone initially explored, highlighting the need to consider the environmental impact at every phase of the mining process.

License to Mine: A Comparison of the Scope of the Environmental Assessment in Sweden, Finland and Russia

The regulatory framework for mining operations is complex;the licensing process in particular typically involves several laws and a number of permits. This paper assumes that the regulatory framework is strongly influenced by the institutional framework of which it is part, and that it suffers from an institutional path dependence that may decrease the efficiency of the system as well as act barrier to the implementation of necessary environmental requirements. The paper provides: 1) a legal analysis of the regulatory framework governing mining operations in Sweden, Finland and Russia;and 2) a comparative analysis of the scope of the environmental assessment within the licensing process in the examined countries. The result of the analysis of the regulatory frameworks shows great similarity between the Swedish and the Finnish systems, both in terms of the overall structure and the implementation of substantive environmental rules. The Russian system differs in this respect, with more declarative rules and seemingly less substantive assessments. The results also indicate that the regulatory frameworks in all three countries show signs of institutional path dependence, but in very different degrees. Though Russia has indeed implemented major changes in the formal structure, very little has changed in practice. The Swedish regulatory framework for mining shows a deficient systematics and conflicting objectives, despite the implementation of a comprehensive environmental legislation. The recently reformed Finnish system seems to have a more holistic approach.

安徽矾矿土壤重金属污染源解析模型对比与优选

矿区资源开采导致土壤污染日益严重,直接影响周边土壤、水体环境的稳定性,精准预测重金属污染源解析对矿山修复、治理具有重要指导作用。在前期研究基础上,为提升土壤介质模型的解释度,进一步选取了土壤重金属源解析评价中成熟度高且精准性好的正定矩阵因子分析法(positive matrix factorization, PMF)及绝对因子分析-多元线性回归(absolute factor analysis-multiple linear regression, APCS-MLR)模型,以充实前期UNMIX多元受体模型分析矾矿土壤重金属污染来源及源贡献率的结果,结合生态风险评价方法,对比定量条件下最适宜解析研究区域源的模型。结果表明:1)生态高风险区域主要集中在研究区南部和东部,Cd是矿山主要风险元素,地累积指数(index of geoaccumulation)均值3.75与潜在生态风险指数(potential ecological risk index)均值731.22解析结果高度一致,但潜在生态危害指数的结果综合性更好。2)对比3种模型的污染源解析结果,PMF模型解析出4个污染源:分别为燃煤源、自然-交通综合源、自然源和大气沉降源,源贡献率分别为38.15%、20.62%、24.28%、16.95%。3)PMF模型的总体变量拟合优度R2达到了0.96,拟合效果最好。PMF模型模拟数据会集中采样点误差,确定最适污染源数目及相应污染物贡献率,使得源解析结果更精准,更适用于复杂的矿山污染土壤情况,符合实际研究情况。该研究结果可为后续矿区开采后污染土壤的修复治理工作提供溯源依据参考。

Environmental issues from coal mining and their solutions

The environmental challenges from coal mining include coal mine accidents,land subsidence,damage to the water environment,mining waste disposal and air pollution.These are either environmental pollution or landscape change.A conceptual framework for solving mine environmental issues is proposed.Clean processes,or remediation measures,are designed to address environmental pollution.Restoration measures are proposed to handle landscape change.The total methane drainage from 56 Chinese high methane concentration coal mines is about 101.94 million cubic meters.Of this methane,19.32 million,35.58 million and 6.97 million cubic meters are utilized for electricity generation,civil fuel supplies and other industrial purposes,respectively.About 39% of the methane is emitted into the atmosphere.The production of coal mining wastes can be decreased 10% by reuse of mining wastes as underground fills,or by using the waste as fuel for power plants or for raw material to make bricks or other infrastructure materials.The proper use of mined land must be decided in terms of local physical and socio-economical conditions.In European countries more than 50% of previously mined lands are reclaimed as forest or grass lands.However,in China more than 70% of the mined lands are reclaimed for agricultural purposes because the large population and a shortage of farmlands make this necessary.Reconstruction of rural communities or native residential improvement is one environmental problem arising from mining.We suggest two ways to reconstruct a farmer's house in China.

磁改性生物质炭渣对酸性矿山废水中Cu^(2+)、Pb^(2+)的吸附研究

针对酸性矿山废水(Acid Mine Drainage, AMD)中Cu^(2+)和Pb^(2+)含量过高,生物质炭渣吸附能力有限等问题,以工业固体废弃物生物质炭渣为原材料,采用高锰酸钾和硫酸亚铁对生物质炭渣进行磁改性,制备生物质炭渣负载MnFe_(2)O_(4)的复合磁性材料(BC-MF),并将BC-MF作为去除酸性矿山废水环境中Cu^(2+)和Pb^(2+)的吸附剂。基于单因素试验方法,探究pH值、温度、初始质量浓度、吸附时间、共存金属离子等因素对BC-MF吸附Cu^(2+)和Pb^(2+)性能的影响,并将吸附动力学、吸附热力学、吸附等温线与扫描电子显微镜(Scanning Electron Microscopy, SEM)、X射线衍射(X-ray Diffraction, XRD)、傅里叶变换红外光谱(Fourier Transform Infrared Spectroscopy, FT-IR)、磁滞回线测试(Vibrating Sample Magnetometer, VSM)、Zeta电位(Zeta potential)等表征方法结合,研究MnFe_(2)O_(4)磁改性生物质炭渣吸附Cu^(2+)、Pb^(2+)的机理。结果显示,改性后的BC-MF对Cu^(2+)和Pb^(2+)的去除率均提升20百分点以上,且吸附饱和质量比分别为18.04 mg/g和24.98 mg/g。表征结果显示:MnFe_(2)O_(4)磁性颗粒成功负载到BC-MF上,并使之具有磁性;BC-MF对Cu^(2+)和Pb^(2+)吸附过程均符合Langmuir等温吸附方程和准二级动力学模型,吸附过程是为化学吸附为主的单层均相吸附;热力学结果表明该吸附过程属于自发进行的熵增过程。

废弃矿山环境修复工作系统探讨

废弃矿山环境修复是还自然环境“历史旧账”的过程,是环境保护的一项至关重要的工作,该工作涉及领域广泛、投入资金量大、修复时间长、工作任务艰巨。为了优化废弃矿山环境修复工作方式,确保该项工作能够有序高效进行,首先,总结以往废弃矿山环境修复模式在构建过程中的不足之处,包括模式选定流程的缺乏和模式相对应技术的不明确;其次,建立一套能够快速且准确构建的修复模式,并且根据修复模式准确锁定修复技术的工作系统,该工作系统是以矿山的实际环境情况和矿山环境修复基本原则为基础、以修复目标为导向、以修复模式为框架、以修复技术为手段的优化组合;最后,以甘肃省定西市岷县某金矿历史遗留矿山的环境修复工程为实例,分析该工作系统对于废弃矿山环境修复工作的效果。废弃矿山环境修复工作系统的合理性与科学性对建成“绿水青山”的生态环境目标和“可持续发展”的经济建设目标有着深远的影响。

滴灌技术在矿山环境治理项目中的应用研究

目前,矿山环境治理项目在养护过程中,绝大部分仍采用水罐车拉水、结合人工灌溉方式,极少采用农田灌溉中日益发展完善的喷灌、滴灌等高效节水灌溉技术,灌溉效率低和用水浪费的问题普遍存在。通过滴灌技术与常规养护方式在节水、省工及绿化等方面的对比研究,评价滴灌技术在矿山环境治理绿化养护过程中的适用性,为滴灌技术在矿山环境治理项目的推广应用提供技术支撑和模式借鉴。

绿色矿山中环境保护技术的应用

“绿色矿山”是指在资源开发的全过程中,实施科学有序开采。我们旨在实现环境生态化、开采方式科学化、资源利用高效化、管理信息数字化和矿区社区和谐化的矿山。就目前的国际大形势而言,构建绿色低碳的工业体系,不仅是实现应对气候变化目标的必要手段,对工业的可持续发展同样意义重大。同样的对于矿业发展而言,环境保护,节能减排迫在眉睫。针对矿产开发的污染形式,依据矿产企业的环境治理出发点,提出矿产企业绿色矿山建设新技术、新方案,为实现矿业企业绿色、文明、和谐、可持续发展奠定了一定基础。

矿山环境正效应开发利用适宜性评价理论与方法

改革开放以来,矿产资源开发为国家经济发展做出巨大贡献,由于多数矿产资源具有不可再生性,相当数量的矿山面临着资源枯竭、关闭。如何开发利用这些矿山所留下的矿山环境正效应资源将成为延长矿业产业链、保障能源绿色低碳发展、实现“碳达峰、碳中和”战略目标的重要支撑。为了科学开发矿山适宜的环境正效应资源,以矿山环境正效应开发利用中的“资源、能源、科普文娱、生态碳汇”4类目标为研究对象,基于矿山供给本体特征、特定市场需求及开发利用条件的“供给(Supply)-需求(Demand)-开发(Development)”(SDD)约束组合,创建了包含6类一级约束、38个相应属性二级约束的矿山环境正效应开发利用评价约束体系;根据开发利用目标导向的原则,依据目标特征组建了18项实施项目单目标评价指标集;构建了单目标适宜性评价模型,引入三角模糊数确定指标权重,并依据适宜性指数划定了“适宜、较适宜、较困难、困难”四类适宜性分级标准。此外,鉴于矿山环境正效应开发利用系统复杂性,剖析了各开发利用目标的逻辑关系,提出了基于经济、生态、社会效益综合最优理念的矿山环境正效应开发利用多目标线性评价理论,通过理想点法或单目标线性规划求解,获取矿山环境正效应开发利用多目标效益综合最优解或最适宜集。最后,从国家战略、社会需求、流域生态、正效应市场开发等角度,展望了矿山环境正效应开发利用及其系统评价落地的重要意义。

滇东典型煤矿区土壤重金属生态风险及来源解析

【研究目的】研究区地处滇东重要煤炭和农业产区,弄清煤矿区土壤重金属空间分布特征、潜在生态风险和污染来源,对煤矿区生态环境保护治理和确保农业安全具有重要现实意义。【研究方法】基于网格布点法于2021年6月在典型煤矿区采集土壤样品497件,分析了土壤pH、SOM、As、Cd、Cr、Cu、Hg、Ni、Pb和Zn,运用污染负荷指数法和潜在生态风险指数法对重金属污染状况和潜在生态风险进行评价,通过主成分分析和正定矩阵因子分析(PMF)模型分析了重金属潜在来源。【研究结果】土壤pH平均值为5.39,以酸性为主,SOM含量平均值是云南省土壤背景值的1.20倍,Cr、Cu、Cd、Ni、Zn和Hg含量平均值和中位数均超过云南省土壤背景值,绝大部分采样点Cd、Cu、Cr、Ni含量超过风险筛选值,分别占94.97%、93.96%、91.35%、79.28%,少部分采样点As、Cd含量超过管制值,分别占0.20%、1.41%。污染负荷指数法评价结果显示,研究区整体呈现轻微污染。潜在生态风险指数法评价结果显示,研究区整体呈现中等风险。主成分分析和PMF模型解析结果显示,研究区土壤重金属主要来源于地质背景,其次为农业活动和大气沉降。【结论】煤矿区土壤中Cd、Hg潜在生态风险较高,土壤重金属主要来源于地质背景,其次是农业活动和大气沉降,建议加强相关污染土地的监测和管理,减少农家肥不合理施用,强化煤炭工业污染排放监管。

高光谱遥感技术在地质环境监测中的应用与展望

高光谱遥感技术是一种功能非常强大的综合性学科技术,其以数据的实时性、光谱信息的丰富性、成本的高效益性、覆盖范围的广泛性等特征以及高分辨率和图谱合一的优势,在各个领域上得到了广泛的应用。文章介绍了高光谱遥感技术成像的基本原理、国内外高光谱成像仪和高光谱卫星的发展历程,重点描述了高光谱遥感技术在矿山环境监测、水环境监测与评价、土壤含水率监测等方面的应用成果。高光谱遥感技术面临着“维数灾难”、精确度不足、时效性受限、高光谱遥感数据解译困难等问题,未来可通过协同多平台、利用人工智能模型等方式提高精确度,构建典型的光谱库提高模型的普适性。

基质配置对潮汐流人工湿地处理稀土矿山含氨氮地表水效果的影响

人工湿地(Constructed Wetland,CW)可对稀土矿工业开采遗留的氨氮污染废水进行高效生态化处理。添加铁碳和生物炭材料构建四组潮汐流人工湿地,研究不同淹没空置比(F/D)条件下铁碳和生物炭添加方式及位置对湿地脱氮效果的影响。结果表明,控制F/D=6 h/6 h(水流淹没湿地床体6 h后排水空置6 h后下一批次进水),进水NH^(+)_(4)-N为40±2.37 mg/L,CW_(FeC2)(NO.2 Fe-C substrate Constructed Wetland)对NH^(+)_(4)-N有较好的脱氮效果,平均去除率86.44%±3.28%,最高去除率89.72%,CW_(B)(Biochar based Constructed Wetland)对总氮(TN)有较好的去除效果,最高去除率51.12%。高通量测序分析结果显示,生物炭基质湿地Alpha多样性指数各指标均大于铁碳基质湿地。具有固氮作用的变形菌门在CW FeC1和CW_(FeC2)中占比70%以上,在CW_(B)中占比40%以上,是最主要的脱氮菌群。在CW_(B)中发挥好氧硝化作用的硝化螺旋菌占比15%以上,酸杆菌门存在近10%,能适应酸性条件且具有一定脱氮作用。本实验的进行对稀土矿山含氨氮废水的生态化处理具有一定的参考应用价值,为相关领域填补空缺并提供一定的数据支持。